A method for detachably connecting optical fibers by using a single-core optical connector or a multiple-core optical connector has been used as one of the methods for connecting optical fibers. FIG. 10 shows a generally known multiple-core optical connector, which is used for detachably connecting multiple-core optical fibers. As shown in the same drawing, a plurality of optical fiber insertion holes (not illustrated) are juxtaposed and formed inside a ferrule 1, bare optical fibers 5 at which the tip end side covering of an optical tape 2 is eliminated are inserted into these optical fiber insertion holes in such a state where they protrude therefrom, and the bare optical fibers 5 are fixed to the ferrule 1 by an adhesive agent, etc. thereby causing a multiple-core optical connector 4 to be composed.
The multiple-core optical connector 4 is set to, for example, a polishing machine shown in FIG. 11, in a state that the optical tape 2 is connected to the ferrule 1, wherein the connection end face 3 side of the ferrule 1 is pressed to the polishing surface 42 of a grinding wheel 41 on the turntable 40 which is rotating, the end face of the optical fiber 5 is polished along with the connection end face 3 of the ferrule 1, and the multiple-core connector 4 is polish-finished when the same is polished to the position Lm shown in FIG. 10.
However, for example, as shown in FIG. 11, since a conventional polishing machine has a grinding wheel 41 disposed on the turntable 40 and is large-sized, the machine is remarkably large and heavy in weight. Therefore, it is very cumbersome to convey the same to the site of connections of optical connectors such as multiple-core connectors 4, etc., and the same is an obstacle in view of improving the working efficiency of connections of optical connectors.
Furthermore, in a conventional method for polishing optical connector end faces, as described above, if a force for pressing an optical connector such as a multiple-core connector 4, etc. to a grinding wheel 41, etc. is weak, there arises such a problem, where the polishing efficiency is bad and it takes longer for polishing since the end face of an optical fiber 5 is polished to the position where the same is polished together with the connection end face of a ferrule 1. On the other hand, if the optical connector is strongly pressed to the grinding wheel 41 side in order to increase the polishing efficiency, there arises another problem that the tip end side of optical fiber 5 may be cracked causing the optical fiber end face side to be damaged. Furthermore, such problems also occurred in implementing an elastic polishing disk described in Japanese Patent Publication No. 192460 of 1986 in order to spherically polish the optical fiber end faces, using the polishing machine shown in FIG. 11.
Furthermore, since, in conventional polishing machines, a grinding wheel, polishing disk, etc. are very large with respect to optical connectors, there arises still another problem that since it is difficult to position optical connectors with respect to a polishing machine, only one side of the optical connector end face is polished if the parallelism of the grinding wheel surface or the surface of a grinding disk with the optical connector end face slightly slips.
The present invention was developed in order to solve the abovementioned problems, and it is therefore an object of the invention to provide a method for polishing the end face of optical connector, by which the optical fiber end faces of optical connector can be easily polished to an appointed shape of end face in a short time so as not to damage the optical fiber end face sides without using any turntable type polishing machine, and to provide a small-sized and easily transportable polishing machine adapted for the polishing method.